<!DOCTYPE html>
<html lang="en" xmlns:v-on="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>keyevent</title>
</head>
<body>
    <div id="app">
        <input type="text" @keyup.alt.a="key">
    </div>
</body>
<script src="../node_modules/vue/dist/vue.js"></script>
<script>
    let vm = new Vue({
        el:"#app",
        data:{
            num:18
        },
        methods:{
         key(){
             alert("cnm");
         }
        }
    })
</script>
</html>